Desk-telephone.



N. PEDERSEN.

DESK TELEPHONE.

APPLICATION IILED 11111.24, 1911.

1,097,359; Pa tentedMay19,1914.

2 SHEETS-SHEET 1.

W 2M M 6% COLUMIIA PLANOGRAPH C0" "IAIHINGTON. D-t- N. PBDERSEN.

v DESK TELEPHONE. A'PPLIouIon rum) in. 24, 1911.

1,097,359. r I, Patented May 19.- .1914.

COLUMBIA PLANDGRAPH C0.,WASl llNCITON, D. O.

UNITED STATES PATENT OFFICE.

NIELS PEDERSEN, OF GENOA, ILLINOIS, ASSIGNOR TO CRACRAIET, LEIGH ELECTRIC COMPANY, OF GENOA, ILLINOIS, A CORPORATION OF ILLINOIS.

DESK-TELEPHONE.

Specification of Letters Patent.

Patented May 19, 1914.

Applicationfiled January 24, 1911. Serial No. 604,361.

To all whom it may concern: 7

Be it known that I, NmLs Pnnnnsnn, a citizen of the United States, residing at Genoa, in the county of Dekalb and $tate of Illinois, have invented a certain new and useful Improvements in Desk-Telephones, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to desk telephones or other similar portable telephones and has for its object the provision of improved facilities within a portable telephone for effecting certain circuit changes by means of springs or similar circuit changing apparatus therein.

I am aware that it has been proposed and practically introduced to utilize a local battery telephone system in which a local battery at the substation is used for talking purposes, which batteryeither alone or in conjunction with an additional battery is used through the agency of prolonged contact making appliances for sending a current impulse of appreciable time interval to the central station for the purpose of actuating suitable signals preferably in the form of drops. I am also aware that a slow acting switching device capable of use in a wall telephone has been in practical operation to operate in accordance with the system set forth at the end of the preceding paragraph. This particular switching device is so arranged that in its movement in one direction a clearing out drop may be actuated and in its movement in the other direction a line drop may be actuated. I am also aware that it has been proposed to provide means to accomplish the results aforesaid in connection with portable telephones.

It is of prime importance in the operation of systems such as outlined above that the same may be utilized in connectionwith portable telephone apparatus and it is the object of my present invention to so construct a portable telephone apparatus that it may be used for sending automatically, when the receiver is removed, a current impulse of appreciable'time interval to the central station to operate a line drop and when the receiver is'replaced to automatically send a current impulse of appreciable time interval to the central station to operate a clearing out drop, said signals being selective in their nature. Of course, my mvention is not limited to sending both of these signals under such central station circuit conditions when the sending of one given impulse answer. My invention is likewise not limited to the specific form of carrying it out set forth in this application as the structure set forth herein is merely typical of a multiplicity of forms which the invention may take.

I will explain my invention more in detail by reference to the accompanying drawings illustrating one form thereof, in which Figure 1 is a front view partly in section of a portable telephone constructed in accordance with my invention; certain portions thereof being left out for the sake of clearness; Fig. 2 is a bottom view of the base of the telephone set forth in Fig. 1; Fig. 8 is a view of the apparatus illustrated in Fig. 2 on lines aa,- Fig. 4 is a detail of construction; Fig. 5 is a perspective view more clearly to indicate features of operation, and: Fig. 6 is a diagrammatic view illustrating the circuit conditions involved.

Referring more particularly to Fig. 6, I show the substation circuit and will explain the same first to indicate what functions the portable telephone switching devices are adapted to perform. In this Fig. 6, I show a receiver 1, a transmitter 2, together with an induction coil 3. The induction coil is shown as mounted on a terminal block 4. Two sets of batteries are used, a talking battery 5 and anauxiliary signal sending battery 6, although the invention of course is not limited to the use of'two batteries. Receiver circuit springs 7 and 8 are used and transmitter circuit closing springs 9 and 10. Three additional springs 11, 12 and 13 are used for automatic signal current impulse sending purposes. When springs 11 and 12 are in contact, for instance, current from the two batteries 5 and 6 is adapted to flow over the line wires 14 and 15 which lead to the central station, and when springs 11 and 13 are in contact, current from the same two batteries in series is projected over the conductor 15 and the ground 16. When the receiver is on the switchhook lever 17 circuit through the springs 7, 8, 9 and 10 is open and neither the transmitter or receiver is in circuit, as is well understood. When the receiver is removed from the lever 17 how ever, springs 7 and 8 contact to close the receiver circuit, and springs 9 and 10 contact to close the transmitter circuit. The spring 11 is actuated to contact with either springs 12 or 13, as will appear hereinafter when it is desired to send selective current impulses so as to selectively operate the line drop and the clearing out drop. Should it be found that a metallic current impulse is sufficient, the spring 13 may either be dispensed with or may be utilized, if it is desired, to send a metallic impulse both when the receiver is removed and when it is restored, in which event, of course, the ground connection for the spring 13 would be removed and said spring would be connected to the spring 12. The spring 11 is adapted not to contact with either the spring 12 or the spring 13 when the switchhook lever 17 is in either its uppermost or lowermost position. But the apparatus is so arranged herein, being adapted for selective signal sending purposes that when the lever moves from one limiting position to the other it establishes during movement and maintains during the movement a closure between springs 11 and 12, but breaks this connection again when it has reached its limiting position, whereas the reverse movement of said lever will during the movement of the said lever only connect springs 11 and 13, but again open the contact when the lever has reached its alternative limiting position. In the limiting positions of the switchhook therefore springs 11, 12 and 13 are unconnected, but during movement in one direction springs 11 and 12 are connected and during movement in the opposite direction springs 11 and 13 are connected. The circuit arrangements thus set forth require that the closure of the circuit through the springs 11 and 12 or 11 and 13 be for an appreciable time interval in order to provide sufficient time for the drops at the central office to operate properly as a mere passing contact in many cases would be insufficient and usually would be unreliable.

The invention herein therefore contemplates means for effecting the necessary circuit changes between springs 7, 8, 9 and 10 and to effect the sending of selective current impulses of appreciable time interval by the extended actuation of spring 11 to associate said spring for a given period either with the springs 12 or 13. The mechanical features only are claimed herein for effecting the results above outlined.

The portable telephone as shown in Fig. 1 comprises the standard 18 within which the lever 17 is mounted and the base 19. The transmitter 2 is supported at the top of the standard 18 and by means of radial arms 20 the devices within the base of the stand are held in place. The lever '17 controls a plunger 21 and this plunger is adapted to engage a roller 22 carried by the spring 7 In the illustration of Fig. 2, the plunger is in its uppermost position and circuit through the springs 7 and 8, and the springs 9 and 10 is closed. Should the plunger be depressed, for instance, as when the receiver 1 is replaced upon the lever 17, then the spring 7 as shown in Fig. 2 is bent in a clockwise direction and this opens the circuit between springs 7 and 8 and by virtue of the plunger 23 opens the circuit between the springs 9 and 10 as this plunger 23 passes through the spring 8 but does not engage the same. The plunger 21 is provided with a knob 24 to operate the roller 22 and also serves to effect circuit changes between the springs 11, 12 and 13 by means of the improved construction which will now be described.

The springs 11, 12 and 13 are suitably insulated from each other and mounted on the arm 25 which forms part of the plate 26 that is rigidly fastened in the base of the telephone. A substantially L shaped arm 27 is pivoted at 28 through the agency of the bracket 29 and carries a roller 30, which roller is arranged to be engaged by the head 24. The L shaped arm 27 is provided with a roller 31 which rolls over the plate 26. A spring 32 normally holds the arm in the position indicated in Fig. 2. The short leg of the arm 27 carries a spring actuating plate 33, which spring actuating plate has an in clined surface on its top face at one extremity and an inclined surface on its bottom face at the other extremity, as will be more clear from an inspection of Fig. 5. The spring 11 has a goose neck extension 34 which is slightly rounded at its extremity. This spring occupies a position with relation to the'plate 33 as will be more clearly apparent from an inspect-ion of Fig. 1. When the plate moves in one direction from its original limiting position, it bends the spring 11 downwardly into contact with spring 13 and maintains this contact while the arm 27 is moving to its limiting position. Slightly prior to the time that the arm 27 has reached its limiting position, however, the plate 33 has passed beyond the extension 34 and the spring resumes its normal non-contact making position.

The above described operation would take place when the arm is moved in a clock-wise direction (Fig. 2) to its limiting dotted position shown in Fig. 2. This occurs when the receiver is replaced upon the hook. YVhen the receiver is removed the plate 33 again engages the extension 34, but this time presses it upwardly against the spring 12 throughout practically its entire motion until shortly before it has reached the limiting position indicated in Fig. 2 while traveling in a contra-clockwise direction, at which time the extension 34 has again left the plate 33 and is in its normal position. It will thus be seen that a movement of the plate 33 in one direction closes circuit through the springs 11 and 12 and a movement in the opposite direction closes circuit through the springs 11 and 13. This circuit closure, however, lasts only throughout the movement and at the time the limiting posit-ion is reached of the movement in either direction the circuit is again open. On account of the long lever arm, the arm 27 being pivoted at 28, a wide sweep is given to the plate 33 and the circuit closure through springs 11 and 12 or 11 and 13 is of an appreciable time interval, sufficiently to actuate the drop at the central station which would remain generally unactuated were the contact merely momentary. The pressure of the head 24 against the roller 30 moves the arm 27 in a clockwise direction and the release of the pressure permits the spring 22 to move the arm 27 in its contra-clockwise movement.

I am not describing the terminal connections in the desk set base nor some of the other features which are not parts of my present invention, but am describing merely the operative features necessary for a proper understanding of my invention. I, of course, do not mean to limit myself to the precise construction as set forth herein as the invention is capable of a great variety of uses and manymodifications may be made A portable telephone having a hook lever, v

a plunger, a lever movable transversely of said plunger having a long spring actuating arm, circuit changing springs controlled by said last aforesaid lever, means on said last aforesaid lever to actuate certain of said circuit changin devices when moving in one direction an other of said circuit chang ing devices when moving in the opposite direction, a roller interposed between said lever and said plunger, a roller mounted at the extremity of said long arm to guide the same, and a retractile sprlng associated with.

said long arm.

In witness whereof, I hereunto subscribe my name this 9th day of January A. D., 1911.

NIELS PEDERSEN.

Witnesses J. P. CRAORAFT, OSCAR M. LEIGH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

